hw/arm/virt: Set virtio-iommu aw-bits default value to 48

On ARM we set 48b as a default (matching SMMUv3 SMMU_IDR5.VAX == 0).

hw_compat_8_2 is used to handle the compatibility for machine types
before 9.0 (default was 64 bits).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Zhenzhong Duan <Zhenzhong.duan@intel.com>
Message-Id: <20240307134445.92296-9-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 0af19436973f3463598b730e24cca530cf31d315..e5cd9352326506bc5b9ebba43c66143776277ef3 100644 (file)
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -85,11 +85,28 @@
 #include "hw/char/pl011.h"
 #include "qemu/guest-random.h"
 
+static GlobalProperty arm_virt_compat[] = {
+    { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "48" },
+};
+static const size_t arm_virt_compat_len = G_N_ELEMENTS(arm_virt_compat);
+
+/*
+ * This cannot be called from the virt_machine_class_init() because
+ * TYPE_VIRT_MACHINE is abstract and mc->compat_props g_ptr_array_new()
+ * only is called on virt non abstract class init.
+ */
+static void arm_virt_compat_set(MachineClass *mc)
+{
+    compat_props_add(mc->compat_props, arm_virt_compat,
+                     arm_virt_compat_len);
+}
+
 #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
     static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
                                                     void *data) \
     { \
         MachineClass *mc = MACHINE_CLASS(oc); \
+        arm_virt_compat_set(mc); \
         virt_machine_##major##_##minor##_options(mc); \
         mc->desc = "QEMU " # major "." # minor " ARM Virtual Machine"; \
         if (latest) { \